Bump version release (#230)

* switch runtime to tfjs

* updating version to 1.2 to prepare release

* update README

---------

Co-authored-by: ziyuan-linn <zl4140@nyu.edu>

README.md

@@ -22,12 +22,12 @@ Before getting started with ml5.js, review our [Code of Conduct](https://github.
 
 <!-- Anchor for automatic version update script, do not remove this comment -->
 
-- You can use the latest version (1.1.0) by adding it to the head section of your HTML document:
+- You can use the latest version (1.2.0) by adding it to the head section of your HTML document:
 
-  **v1.1.0**
+  **v1.2.0**
 
   ```html
-  <script src="https://unpkg.com/ml5@1.1.0/dist/ml5.js"></script>
+  <script src="https://unpkg.com/ml5@1.2.0/dist/ml5.js"></script>
   ```
 
 <!-- Anchor for automatic version update script, do not remove this comment -->

package.json

@@ -1,6 +1,6 @@
 {
   "name": "ml5",
-  "version": "1.1.0",
+  "version": "1.2.0",
   "description": "A friendly machine learning library for the web.",
   "main": "dist/ml5.min.js",
   "scripts": {